Rotomolding a thermoplastic hollow molding method. Rotomolding is a fairly versatile manufacturing process. The rotomolding process involves first adding plastic raw materials to the mold, and then continuously rotating the mold and continuing heating, so that the plastic raw materials in the mold are gradually and evenly distributed and adhered to the entire surface of the cavity under the action of gravity and heat. In the above, the product is shaped into the desired product shape, and then cooled and shaped to complete the finished product. Compared with other mould processes, the rotomoulding process provides us with more imagination space, which results in a corresponding design space. That is, as long as we are under the correct design concept, we can combine several parts into a complete mold, which greatly reduces the cost of production. With the continuous development of rotomolding molding technology, the types of rotomoulding molds have been continuously increasing. The rotomolding process has been applied in transportation, traffic safety equipment, entertainment industry, river channel dredging industry, construction industry, and so on.